nagosnell

I want to find a stock locking diff from another Jeep to put in my 98 XJ (4.0 and 4x4). This leads to a few questions:

1.) How can I tell what rear diff is currently in it (ratio and Dana or Corporate)? Obviously, I know it is not a locking one but that is about it. Also, it's a regular Sport with no off-road pkg so more likely it's not a Dana (assumption, but you know the saying).

2.) I'm more likely to get a locking diff from a local junkyard or pick-it-yourself...will the Wrangler diffs or Grand diffs fit mine? Also, how will I know that it is a locking unit (if I rotate one wheel, will the other one spin in the same direction)?

3.) Finally, is going with a junkyard diff the cheaper alternative? I don't do major off-roading nor do I have oversize tires. The last two Jeeps I owned had a stock locker and I never had any problems with them.

Thanks for the help.

djb383

May need to look at aftermarket for a XJ locking diff.....the few traction enhanced XJ diffs that went out the factory door were most likely limited slip diffs. Limited slip is certainly better than nothing (open diff) but falls short of a locking diff off road.

bheath

you probably have an 8.25 which is a great rear-end. search on here. there are many threads about ''what rear-end do i have?''. personally i would get a new aftermarket locker... somebody correct me if im wrong but most ''lockers'' that came stock in xj's are limited slip. not truly 'locked'. since you don't do harcore off-roading and you are running stock tires and all a 8.25 ''which i think you have'' locked, will almost be overkill... but it's also plenty if you ever decide to go up to about 35" tires... (IMHO)

djb383

There are 3 basic types of diffs: open, limited slip and locking. The only similarity between limited slip and locking, is they are both traction enhanced diffs. Not much similarity after that as they are two very different types of diffs. There are numerous brands and styles of both limited slip and locking diffs.

I believe the factory only offered a optional limited slip rear diff on the XJ.

nagosnell

I don't know why I referred to the factory units as "locking"… I was wrong there. However, I liked the limited slips I had in my last two Jeeps. I occasionally drive down muddy trails to get to my hunting plots and the lsd’s worked just fine. Also, I liked the way these diffs acted on icy and gravel roads. They allow me to kick the rear end out in curves without going overboard.

With that being said, I would imagine that an aftermarket locking diff would be more expensive than pulling a stock lsd out of a low mileage Jeep. Right?

Bheath, your probably right about mine being a 8.25, but I would like to find out what the ratio is so that I don’t get a diff that has a different one from the front diff. It seems like I’ve seen a build sheet somewhere in my Jeep. Maybe that will tell me. Also, I only have 30" tires and that's as big as I'm going.

So, my original questions still apply… to finding a limited slip.

What do y’all think?